Herpes simplex virus type 1 (HSV-1), commonly found in oral lesions, is being recovered from genital lesions with increasing frequency in young adult males and females. Clinical histories suggest that, in general, this phenomenon is related to oral-genital sex practices. Since HSV-1 is now commonly recovered from the genitalia of this population, will HSV-2, especially because of oral-genital contact, be found with increasing frequency in the oral cavity of this group of individuals? Oral samples on cotton swabs will be acquired from male or female college students that fall into one of three categories; 1) individuals with multiple white ulcerated lesions on the tonsils, pharynx, soft and hard palate, gingiva, tongue, lips, and buccal mucosa with accompanying fever (101-103f) and anterior or posterior cervical adenopathy, 2) individuals with a single contained lesion on the lips or gingivia, 3) individuals with tonsillitis or pharyngitis. Virus will be isolated in tissue culture, identified as HSV by serum neutralization, and typed as HSV-1 or HSV-2 by monoclonal antibody immunofluorescence and restriction endonuclease analysis of viral DNA. In order to determine if the infection is primary or recurrent, serum samples will be acquired from each patient at the time of the initial visit and after fourteen days. Immunoglobuling IgG and IgM will be separated by Sephadex G 200 column chromatography and analyzed for HSV neutralizing activity. The presence of IgM followed by IgG will be suggestive of a primary infection while the presence of only IgG will suggest a recurrent infection. Acquired data will establish the frequency of occurrence of HSV-2 in oral infections in this population, the relationship of the disease to preexisting antibody, and clinical characteristics of the disease. Such information is critical when considering the recent development of type specific anti-HSV drugs and the potential relationship of HSV-2 to some squamous cell carcinomas.